Unit 1: Traumatic Brain Injury (TBI) Flashcards
Traumatic Brain Injury (TBI)
- can cause financial and human costs
- many unable to return to previous roles in the family and in their personal and professional lives
- care of the patient occurs best in environments where seamless continuity and progression of care can occur, from emergency medical services (EMS) to the emergency department (ED) to the operating room (OR), the critical care unit, acute care unit or facility, and outpatient services
- classified by the Glasgow coma scale
Glasgow Coma Scale Score for TBI categories of injury
> Mild 13-15
Moderate 9-12
Severe = or < 8 (coma)
Coup
damage to the primary area of impact; primary injury; “blow”
- shearing
- twisting
- diffuse axonal injury
- blood vessel dissection
Contrecoup
damage sustained to the area opposite to impact; secondary injury; “counter blow”
- contusion
- swelling
- blood clots
- epidural and subdural hematoma
Primary Brain Injury
d/t the initial insult
Secondary Brain Injury
encompasses all processes that occur after the injury
Treatment protocols are aimed at what?
preventing or managing hypotension and hypoxemia in the immediate period after injury
Traumatic Brain Injury Types
- Scalp Laceration
- Skull Fractures (Open, Closed, Basilar)
- Concussion
- Contusion
- Hematomas
- Neuronal Injury
- Vascular Injury
Open Skull Fracture
- a disruption of the scalp such that the skull is exposed to the atmosphere
- these bleed profusely d/t numerous blood vessels in close proximity to the scalp
Closed Skull Fracture
- may be palpated through the scalp
- visualized on x-ray or other radiographical imaging
Basilar Skull Fractures
- base of skull
- carries additional risk of infection if there is evidence of CSF leak from the ears, nose, or sinus tract
- late sign = bruising around the eyes (Racoon’s eyes) or ears (battle’s sign)
Epidural Hematoma
blood collects in the potential space between the skull and the dura mater
- blood fills a particular epidural space and begins to compress or displace brain tissue inward, causing a concave appearance on radiographical imaging
- when an artery is damaged flow of blood is very rapid and under pressure, speed with which blood collects and potential amount can cause rapid increase in ICP and herniation of brain tissue laterally then down if not stopped
- epidural hematoma = neurosurgical emergency; requires prompt evacuation of blood clot and repair to damaged vessels
- clinical manifestation: “talk and die” phenomenon
- Tx: Burr holes to relieve pressure and evacuate the blood w/ cauterization of the artery
Clinical Presentation when there is an Epidural Hematoma
- comatose state on initial presentation to a lucid (aware of surroundings) state, depending on size and location of hematoma as well as rate and volume of blood collection in epidural space
- can initially loose consciousness, regain consciousness and appear lucid, and then very rapidly deteriorate to unresponsiveness w/ signs of cerebral herniation syndrome
- “talk and die” phenomenon
Subdural Hematoma
collection of blood beneath the dura and above the arachnoid layer
- can continue into brain tissue
- the brain is connected to the inner surface of the dura by a network of veins called bridging veins; when head is impacted by a blunt force, the brain moves within the skull and dural covering; when brain moves, tension is placed on bridging veins = stretching and tearing, releasing a steady flow of blood around the brain in the subdural space, increasing ICP
- symptoms appear over the course of hours or even a few days
- Tx of neurosurgical intervention depends on clinical stability of the patient and state of neurological examination; based upon neurological exam; monitoring done if there are no motor deficits and patient is A&Ox3
Contusion
bruise on the surface of the brain that has the potential to transform into a hematoma
- associated w/ development of cerebral edema
- serial neurological assessments; evaluate for increased ICP
Concussion
injury w/ no findings with imaging but w/ damage at the cellular level d/t brain hitting inside of skull
- LOC does not nee to occur
- Symptoms: headache, amnesia, confusion, vertigo, inability to concentrate
- Treatment: Brain rest
Neuronal Injury
Diffuse axonal injury (DAI)
-direct injury to neurons d/t shearing and rotational forces
-poor outcome
-MRI and PET scan help characterize the neuronal response to head injury
-severity depends on location and extent of injury
-swelling and microscopic hemorrhages can occur
>Sympathetic storming: sympathetic dysregulation; episodic tachycardia, tachypnea, and hyperthermia; spontaneous motor posturing (flexor or extensor)
-require supportive care of all systems in critical care setting
-require intubation and ventilatory support
-Tx: maintain ICP WNL; prevent complications
-coma often results
Vascular Injury
Traumatic Subarachnoid Hemorrhage (SAH): focal in location
- diffuse layering of blood in the arachnoid layer
- occurs as a result of disruption of veins and arteries transversing the arachnoid layer
- local vasospasms
- poor prognosis
- care is supportive w/ cerebral edema commonly occurring
- clot formation d/t the injury can occur; risk for stroke
Complications from Traumatic Brain Injury (TBI)
- Increased ICP
- Herniation Syndromes
- Meningitis (w/ open fractures and dural tears)
- Dural tears
- Seizures (blood is irritant to brain tissue)
- Diabetes Insipidus (d/t lack of ADH from pituitary)
- Syndrome of Inappropriate diuretic hormone (SIADH) (excessive ADH from pituitary)
Complications: Diabetes Insipidus
- symptoms: increased urinary output of dilute urine; hypernatremia; low urine specific gravity (<1.005)
- when swelling in the brain places pressure directly on the posterior portion of the pituitary gland or on blood vessels supplying this area, disorders of sodium and water balance occur; antidiuretic hormone (ADH) is secreted from the posterior portion of the pituitary gland
- Diabetes insipidus occurs in the absence of ADH; urinary output rapidly increases, causes loss of free water and severe dehydration; hypernatremia and low urine specific gravity (<1.005) [urine too diluted]
- Tx: replacing fluid losses and ADH w/ exogenous form (IV, SubQ, intranasally)